Image reading apparatus and image forming apparatus

ABSTRACT

An image reading apparatus includes a first stacking unit having a stacking surface, and an abutment portion that abuts a document stacked on the stacking surface, a feeding unit, a reading unit, a second stacking unit, a first detection unit, a rotating shaft, a drive unit, and a control unit. The second stacking unit receives the document fed by the feeding unit and read by the reading unit. The first detection unit detects presence or absence of the document stacked on the first stacking unit. The drive unit rotates the first stacking unit around the rotating shaft rotatably supporting the first stacking unit. At a predetermined timing after the first detection unit detects the absence of the document on the first stacking unit, the control unit controls the drive unit to rotate the first stacking unit in a direction with which the abutment portion is lowered.

BACKGROUND Field

The present disclosure relates to an image reading apparatus that readsan image of a document, and an image forming apparatus including theimage reading apparatus.

Description of the Related Art

An image reading apparatus included in scanners and copying machines isconventionally provided with an automatic document feeder (hereinafterreferred to as an ADF) that successively feeds documents stacked on adocument tray, conveys each document to an image reading position, readsan image of the document, and discharges the document to a dischargetray. Among the ADFs are configured to align documents in the widthwisedirection by a user operation of placing documents on a horizontaldocument tray and operating a side regulation plate provided on thedocument tray.

A technique for aligning documents by the documents' own weight with adocument tray that is inclined to a front side at a user's documentsetting operation is known for a document tray for an ADF. JapanesePatent Application Laid-Open No. 2003-323084 discusses a technique forenabling a user to view a document stacking surface of a document trayeven from a low viewpoint position for an ADF configured to incline adocument tray to the front side. More specifically, when the user havinga low viewpoint position changes an inclination angle of an operationpanel unit for easier viewing, an inclination angle of the document trayis automatically changed.

In the configuration discussed in Japanese Patent Application Laid-OpenNo. 2003-323084, the user needs to perform an operation for incliningthe operation panel unit to incline the document tray to the front side.Further, when the user holds a document in a hand, the user performs theoperation for inclining the document tray to the front side whileholding the document in a hand. This adversely affects operability ofdocument setting.

SUMMARY

The present disclosure is directed to improving operability of an imagereading apparatus on which documents are set in a state where a documenttray is inclined to the front side, and operability of an image formingapparatus including the image reading apparatus.

According to an aspect of the present disclosure, an image readingapparatus includes a first stacking unit having a stacking surface onwhich a document is to be stacked, and an abutment portion on which anend of the document in a widthwise direction of the document stacked onthe stacking surface abuts, a feeding unit configured to feed thedocument stacked on the first stacking unit in a feeding directionperpendicularly intersecting the document widthwise direction, a readingunit configured to read an image of the document fed by the feedingunit, a second stacking unit configured to receive the document read bythe reading unit and discharged to the second stacking unit, a firstdetection unit configured to detect presence or absence of the documenton the first stacking unit, a rotating shaft extended in the feedingdirection and configured to rotatably support the first stacking unit, adrive unit configured to rotate the first stacking unit around therotating shaft, and a control unit configured to control the drive unit,wherein, at a predetermined timing after the first detection unitdetects the absence of the document on the first stacking unit, thecontrol unit controls the drive unit to rotate the first stacking unitin a direction with which the abutment portion is lowered.

Further features of the present disclosure will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view illustrating an image forming apparatusaccording to the present exemplary embodiment.

FIG. 2 is a cross-sectional view illustrating an image reading apparatusaccording to the present exemplary embodiment.

FIG. 3 is a top view illustrating a document tray according to thepresent exemplary embodiment.

FIG. 4 is a right side view illustrating a state where a document is setin the image reading apparatus according to the present exemplaryembodiment.

FIG. 5 is a right side view illustrating a state where the document isfed in the image reading apparatus according to the present exemplaryembodiment.

FIG. 6 illustrates a rotating mechanism of the document tray accordingto the present exemplary embodiment.

FIG. 7 is a block diagram illustrating control components of the imageforming apparatus according to the present exemplary embodiment.

FIG. 8 is an example flowchart illustrating a document reading operationaccording to the present exemplary embodiment.

FIG. 9 illustrates a modification of the flowchart illustrating thedocument reading operation according to the present exemplaryembodiment.

DESCRIPTION OF THE EMBODIMENTS

Preferred exemplary embodiments of the present disclosure will bedescribed below with reference to the accompanying drawings.

<Configuration of Image Forming Apparatus 101>

The overall configuration of an image forming apparatus 101 according tothe present exemplary embodiment will be described below with referenceto FIG. 1. FIG. 1 is a cross-sectional view illustrating the imageforming apparatus 101 according to the present exemplary embodiment. Inthe following descriptions, a position where a user faces an operationunit 104 for performing various input/setting operations on the imageforming apparatus 101 is referred to as the “front side” of the imageforming apparatus 101, and a rear face side is referred to as the “rearside” of the image forming apparatus 101. More specifically, FIG. 1illustrates the internal configuration of the image forming apparatus101 when viewed from the front side.

The image forming apparatus 101 includes an apparatus main body 101A andan image reading apparatus 103, as illustrated in FIG. 1. The imagereading apparatus 103 disposed on the top of the apparatus main body101A includes a reader 20 and an automatic document feeder (hereinafterreferred to as an ADF) 1 (described in detail below). The image readingapparatus 103 optically scans a document D to read image information.The document D is paper, such as a print sheet and an envelope, aplastics film, such as an overhead projector (OHP) sheet, and a sheet,such as a cloth. The image information converted into an electricalsignal by the image reading apparatus 103 is transferred to a controlunit 132 illustrated in FIG. 7 (described below) included in theapparatus main body 101A. The apparatus main body 101A forms an image ona sheet P as a recording material, based on the image read by the imagereading apparatus 103.

The apparatus main body 101A includes an image forming unit 133 thatforms an image on the sheet P as a recording material, and a sheetfeeding unit 34 that feeds the sheet P to the image forming unit 133.The sheet feeding unit 34 includes sheet storage units 137 a, 137 b, 137c, and 137 d capable of storing sheets with different sizes. A sheetstored in the sheet storage units 137 a, 137 b, 137 c, and 137 d ispicked up by a pickup roller 32, separated from other sheets by a feedroller 33 a and a retard roller 33 b, and then transferred to acorresponding conveyance roller pair 131. Then, the sheet P issuccessively transferred to a plurality of conveyance roller pairs 131disposed along the sheet conveyance path and then conveyed to aregistration roller pair 136.

A sheet P placed on a manual feed tray 137 e by the user is fed to theinside of the apparatus main body 101A by a feed roller 138 and thenconveyed to the registration roller pair 136. The registration rollerpair 136 stops a leading edge of the sheet P to correct skew, andrestarts conveying the sheet P in synchronization with progress of animage forming operation for a toner image forming process by the imageforming unit 133.

The image forming unit 133 that forms an image on the sheet P is anelectrophotographic image forming unit including a photosensitive drum121 as a photosensitive member. The photosensitive drum 121 can rotatealong the conveyance direction of the sheet P. A charging device 118, anexposure device 123, a development device 124, a transfer chargingdevice 125, a separation charging device 126, and a cleaner 127 aredisposed around the photosensitive drum 121. The charging device 118uniformly charges the surface of the photosensitive drum 121. Theexposure device 123 exposes the photosensitive drum 121 to light, basedon image information input from the image reading apparatus 103, to forman electrostatic latent image on the photosensitive drum 121.

The development device 124 including developer containing toner developsthe electrostatic latent image into a toner image by supplying chargedtoner to the photosensitive drum 121. The toner image borne by thephotosensitive drum 121 is transferred onto the sheet P conveyed fromthe registration roller pair 136 by a bias electric field formed by thetransfer charging device 125. The sheet P with the toner imagetransferred thereon is separated from the photosensitive drum 121 by abias electric field formed by the separation charging device 126, andthen conveyed to a fixing unit 129 by a pre-fixing conveyance unit 128.An adhering substance, such as residual toner, on the photosensitivedrum 121 (toner untransferred onto the sheet P) is removed by thecleaner 127. Then, the photosensitive drum 121 prepares for the nextimage forming operation.

The sheet P conveyed to the fixing unit 129 is subjected to fixingprocessing including pressurization and heating of the toner image,while being held and conveyed by roller pairs. After toner melts andthen firmly sticks to the sheet P, the image is fixed to the sheet P.When image output is completed, the sheet P having a fixed image isdischarged to a discharge tray 130 that projects to the outside of theapparatus main body 101A, via a discharge roller pair 40. When formingan image on the back surface of the sheet P in double-sided printing,the sheet P that passed through the fixing unit 129 is reversed by areversing unit 139, and then conveyed to the registration roller pair136 by a double-sided conveyance unit 140. Then, the sheet P withanother image formed thereon again by the image forming unit 133 isdischarged to the discharge tray 130.

The above-described image forming unit 133 is an example of an imageforming unit. For example, an ink-jet image forming unit or an offsetprinting mechanism may be used as the image forming unit 133.

<Configuration of Image Reading Apparatus 103>

The overall configuration of the image reading apparatus 103 will bedescribed below with reference to FIG. 2. FIG. 2 is a cross-sectionalview illustrating the image reading apparatus 103. Sizes, materials,shapes, and relative arrangements of elements described in the followingexemplary embodiments are not limited thereto. Unless otherwisespecifically described, the scope of the present disclosure is notlimited to the exemplary embodiments described below.

As illustrated in FIG. 2, the ADF 1 includes a document tray 2 as afirst stacking unit, a conveyance unit 12, and a discharge tray 3 as asecond stacking unit. The discharge tray 3 is disposed below thedocument tray 2. The ADF 1 is attached to be openable and closable tothe upper surface of the reader 20. The ADF 1 conveys the document D toa reading position on a document feeding-reading glass disposed on theupper surface of the reader 20. The document D is set to the documenttray 2 in the ADF 1. The document tray 2 is supported by a rotatingshaft 11 extending along a feeding direction F, to be rotatable withrespect to the conveyance unit 12. The rotating shaft 11 is disposed ina vicinity of a widthwise center of the document tray 2. The feedingdirection F according to the present exemplary embodiment is a directionin which the document D is fed by a feed roller 4 (described below) anda direction along a document stacking surface 2 a at paper feeding. Thefeeding direction F perpendicularly intersects a widthwise direction ofthe document tray 2 at paper feeding. The widthwise direction is a mainscanning direction of when the image reading apparatus 103 reads animage of the document D.

The document tray 2 is supported by the rotating shaft 11 to berotatable with respect to the conveyance unit 12. Since the documenttray 2 is fixed to the rotating shaft 11, the rotation of the rotatingshaft 11 integrally rotates the document tray 2. The document tray 2 isrotated by a driving force from a motor 13 as a drive unit. While, inthe present exemplary embodiment, the motor 13 is disposed inside theconveyance unit 12, the arrangement of the motor 13 is not limitedthereto. For example, the motor 13 may be disposed inside the documenttray 2 or disposed on a side of a drive unit for applying a rotationaldriving force to each conveyance roller (described below).

As illustrated in FIG. 2, the ADF 1 includes a document detection sensor16 (first detection unit), a discharged document detection sensor 17,and a discharge sensor 18 (second detection unit). The documentdetection sensor 16, the discharged document detection sensor 17, andthe discharge sensor 18 are connected to input ports of a centralprocessing unit (CPU) and are used to monitor a behavior of the documentD. The document detection sensor 16 is disposed on the document tray 2to detect presence or absence of the document D on the document tray 2.The discharged document detection sensor 17 is disposed on the dischargetray 3 to detect presence or absence of the document D on the dischargetray 3. The discharge sensor 18 is disposed on an upstream side of adischarge roller pair 10 in a document conveyance path to detect atrailing end of the document D. The discharge sensor 18 is used todetect that the document D has been discharged. When the documentdetection sensor 16 detects that the document tray 2 has run out ofdocuments D during a feeding operation, a CPU 21 (described below) maydetermine that the document D fed immediately before the detection isthe last document.

As illustrated in FIG. 2, the ADF 1 includes the feed roller 4, a feedroller 5, a separation roller 6, conveyance roller pairs 7, 8, and 9,and the discharge roller pair 10. An image reading section E is disposedon a downstream side of the conveyance roller pair 8 in the conveyancedirection. The image reading section E includes a front surface readingunit 14 disposed on the reader 20, and a back surface reading unit 15disposed on the ADF 1. The document D on the document tray 2 is sent tothe feed roller 5 by a rotational driving force of the feed roller 4 asa feeding unit. The document D is separated one by one by the frictionbetween the feed roller 5 and the separation roller 6 urged from belowby a spring. The separated document D is sent to the image readingsection E by a rotational driving force of the conveyance roller pairs 7and 8. The document D having been sent to the image reading section E issubjected to image reading on both surfaces by the front surface readingunit 14 and the back surface reading unit 15 as reading units. Then, thedocument D is conveyed to the discharge roller pair 10 by the conveyanceroller pair 9 and discharged to the discharge tray 3 by the dischargeroller pair 10. According to the present exemplary embodiment, a seriesof operations from when the document D set on the document tray 2 is fedby the feed roller 4 until when the document D is discharged to thedischarge tray 3 by the discharge roller pair 10 is referred to as a“document reading operation”.

<Configuration of Document Tray 2>

The configuration of the document tray 2 will be described below withreference to FIGS. 3 to 6. FIG. 3 is a top view illustrating thedocument tray 2. As illustrated in FIG. 3, the document tray 2 includesa document stacking surface 2 a and a document abutment portion 2 b as astop member. The document abutment portion 2 b is fixed to the frontside of the document tray 2. The document stacking surface 2 a has afirst edge 200 a close to the document abutment portion 2 b at adownstream end 200 in the feeding direction F, and a second edge 200 bon the opposite side of the first edge 200 a in the widthwise direction.

FIG. 4 is a right side view of the image reading apparatus 103illustrating a state of the document tray 2 when the user sets thedocument D. The user sets the document D in a state where the documenttray 2 is inclined to the front side. In this state, the document tray 2is in a second state of being inclined to the front side, as illustratedin FIG. 4. When viewed from a direction along the feeding direction F,since the document stacking surface 2 a is inclined to the front side byan angle 0 with respect to the horizontal direction, the document D setby the user moves to the front side by its own weight. Since thedocument abutment portion 2 b is disposed on a side closer to theoperation unit 104 of the document tray 2 (the front side), onewidthwise end of the document D moved by its own weight abuts on thedocument abutment portion 2 b, and thus the documents D are aligned.This enables skipping a conventional action to align the documents D,which has been intentionally performed by the user, making it easier toset the documents D. In a state where the document stacking surface 2 ais inclined by the angle 0 with respect to the horizontal direction, thedocument stacking surface 2 a is not smoothly connected with theconveyance path of the conveyance unit 12. More specifically, thedownstream end of the document stacking surface 2 a in the feedingdirection F deviates from an upstream end of a guide that forms theconveyance path of the conveyance unit 12. Thus, the ADF 1 cannotperform a feeding operation in the second state where the document tray2 is inclined to the front side.

Although the angle θ is 30 degrees according to the present exemplaryembodiment, the angle θ is not limit thereto but may be 0<θ<40. Theupper limit of the angle θ, 40 degrees, is the maximum inclination angleat which the set document D abutting on the document abutment portion 2b does not bend. According to the present exemplary embodiment, a lengthof the document abutment portion 2 b in the feeding direction F is setto 150 mm in consideration of the visibility when the document D is set,the present disclosure is not limited thereto.

As described above, the user sets the document D in a state where thedocument tray 2 is inclined to the front side. However, in a state wherethe document tray is 2 inclined to the front side, the ADF 1 cannotperform the feeding operation. Thus, after the document D is set, thedocument tray 2 rotates while the document D is set on the document tray2, to bring a position of the document abutment portion 2 b to be higherthan that in the state illustrated in FIG. 4. More specifically, thedocument tray 2 rotates in a direction (a direction of an arrow B inFIG. 4) with which the first edge 200 a on the side of the documentabutment portion 2 b in the widthwise direction becomes higher than thesecond edge 200 b on the opposite side. After the document tray 2rotates in the direction of the arrow B in this way, the document tray 2is in a first state (a state in FIG. 5) where a level of the front sideis almost the same as a level of the rear side. Then, the ADF 1 starts afeeding operation for the document D. More specifically, the ADF 1 canperform feeding operation when the document tray 2 is in the firststate. In this operation, the document tray 2 starts rotating inresponse to a user's instruction for starting the document readingoperation from the operation unit 104.

According to the present exemplary embodiment, when viewed from thedirection along the feeding direction F, the angle 0 of the documentstacking surface 2 a with respect to the horizontal direction is set tozero degree when the document tray 2 is in the first state. However, itis sufficient that the document stacking surface 2 a is smoothlyconnected with the conveyance path of the conveyance unit 12 at the timeof when a feeding operation is started. Thus, when a feeding operationis started, the document stacking surface 2 a may be slightly inclinedwith respect to the horizontal direction within a range where a feedingoperation can be performed.

After the ADF 1 fed all of the set documents D, and a predetermined timehas elapsed since the document detection sensor 16 detected that thedocument tray 2 had run out of documents D, the document tray 2 rotatesto lower the position of the document abutment portion 2 b. Morespecifically, the document tray 2 rotates in a direction (a direction ofan arrow C in FIG. 5) with which the first edge 200 a on the side of thedocument abutment portion 2 b in the widthwise direction becomes lowerthan the second edge 200 b on the opposite side. After the document tray2 rotates in the direction of the arrow C in this way, the document tray2 is in the second state again where the feeding operation cannot beperformed.

FIG. 6 is a right side view of the image reading apparatus 103,illustrating a state where the front side of the document tray 2 israised by the user. As illustrated in FIG. 6, a gear 11 a with a clutchis provided on the same axis of the rotating shaft 11. Thisconfiguration enables the document tray 2 to freely rotate in a statewhere the clutch is disengaged. This enables the user to raise the frontside of the document tray 2 and then take out the document from thedischarge tray 3 even after the document tray 2 enters the second state.

<Control Components of Image Reading Apparatus 103>

Control components of the image reading apparatus 103 will be describedbelow with reference to FIG. 7. FIG. 7 is a block diagram illustratingcontrol components of the image reading apparatus 103 and the imageforming apparatus 101 including the image reading apparatus 103according to the present exemplary embodiment.

In the image reading apparatus 103, a CPU 21 as the central processingunit executes a program to entirely control each unit of the reader 20and the ADF 1. A read only memory (ROM) 24 is a storage device forstoring control details to be executed by the CPU 21 as a program anddata to be used for program execution. A random access memory (RAM) 25is a storage device that is used as a work area for the CPU 21 toperform control.

To implement the document conveyance function, a conveyance motor 19 asa drive source for driving each conveyance roller disposed in the ADF 1is connected to the CPU 21, and a motor 13 as a drive source forrotating the document tray 2 is also connected to the CPU 21. The CPU 21controls driving of the conveyance motor 19 and the motor 13. Thedocument detection sensor 16, the discharged document detection sensor17, and the discharge sensor 18 are also connected to the CPU 21. TheCPU 21 receives signals from these sensors and controls each unit, basedon the received signals.

An optical system motor 22 and an optical system HP sensor 23 to movethe front surface reading unit 14 in a sub scanning direction isconnected to the CPU 21. The optical system HP sensor 23 detects aposition of the front surface reading unit 14 in a movement direction ofthe front surface reading unit 14 by the optical system motor 22. Thefront surface reading unit 14 and the back surface reading unit 15 areimage sensor units for scanning an image of the document D to performimage reading on a line basis.

The control unit 132 is an information processing apparatus thatentirely controls the image forming apparatus 101 as an image readingsystem including the reader 20 and the ADF 1. The CPU 21 exchangescontrol commands and control data for image reading control via thecontrol unit 132 and a communication line 51. For example, the controlunit 132 receives an instruction for starting an image reading operationby the user from the operation unit 104 and transmits a request forstarting image reading to the CPU 21.

The CPU 21 can measure an elapsed time t1 from when the last document onthe document tray 2 is fed. The CPU 21 also determines whether theelapsed time t1 from when the last document has been fed is equal to orlonger than a first predetermined time T1 (10 seconds according to thepresent exemplary embodiment). In a case where the elapsed time t1 fromwhen the last document has been fed is equal to or longer than the firstpredetermined time T1, the CPU 21 drives the motor 13 to incline thedocument tray 2 to the front side.

<Document Reading Processing Procedure>

A processing procedure for reading an image of the document D will bedescribed below with reference to FIG. 8. FIG. 8 is a flowchartillustrating a processing procedure for reading an image of the documentD stacked on the document tray 2. Processing of this flowcharts isexecuted by the CPU 21.

In a case where the CPU 21 as the control unit receives a signalgenerated when the user sets the document D on the document tray 2, fromthe document detection sensor 16 (YES in step S1001), the processingproceeds to step S1002. In this operation, the document tray 2 is in thesecond state of being inclined to the front side.

In a case where the control unit 132 receives an instruction forstarting a document reading operation by the user (YES in step S1002),the processing proceeds to step S1003. In step S1003, the CPU 21 drivesthe motor 13. The driving force from the motor 13 rotates the documenttray 2 in the direction of the arrow B in FIG. 4. Thus, the documenttray 2 shifts from the second state where the feeding operation cannotbe performed to the first state where the feeding operation can beperformed.

When the document tray 2 shifts to the state where the feeding operationcan be performed in step S1003, the processing proceeds to step S1004.In step S1004, the CPU 21 starts a document reading operation. When theCPU 21 starts the document reading operation, the image readingapparatus 103 conveys the document D stacked on the document tray 2 withthe above-described rollers and reads an image of the document D.

In a case where the CPU 21 receives a signal indicating that thedocument tray 2 has fed the last document and run out of documents D,from the document detection sensor 16 (YES in step S1005), theprocessing proceeds to step S1006. The signal indicating that thedocument tray 2 has run out of documents D means that the signal outputfrom the document detection sensor 16 has changed from a signalindicating presence of documents D to a signal indicating absence ofdocuments D. Meanwhile, in a case where there is an unread document D onthe document tray 2 (NO in step S1005), the CPU 21 repeats or performsthe feeding operation for the document D until the CPU 21 receives asignal indicating that the document tray 2 has run out of documents D,from the document detection sensor 16.

In step S1006, the CPU 21 starts measurement of the elapsed time t1 fromwhen the last document was been fed. In a case where the CPU 21 receivesa signal indicating that the last document has been discharged, from thedischarge sensor 18 (YES in step S1007), the processing proceeds to stepS1008. In step S1008, the CPU 21 ends the document reading operationwith the image reading apparatus 103.

In step S1009, the CPU 21 determines whether the elapsed time t1 fromwhen the last document has been fed is equal to or longer than the firstpredetermined time T1 (10 seconds according to the present exemplaryembodiment). In a case where the CPU 21 determines that the elapsed timet1 from when the last document has been fed is equal to or longer thanthe first predetermined time T1 (YES in step S1009), the processingproceeds to step S1010. More specifically, the CPU 21 does not performthe processing until the elapsed time t1 from when the last document hasbeen fed reaches the first predetermined time T1.

In step S1010, the CPU 21 drives the motor 13. The driving force fromthe motor 13 rotates the document tray 2 in the direction of the arrow Cto shift the document tray 2 to the state where the document tray 2 isinclined to the front side. Thus, the document tray 2 changes from thefirst state where the feeding operation can be performed to the secondstate where the feeding operation cannot be performed. Then, the CPU 21ends the processing of this flowchart. While the first predeterminedtime T1 is 10 seconds in the present exemplary embodiment, the value isnot limited thereto.

<Modification of Document Reading Processing>

Another example of a predetermined timing for inclining the documenttray 2 will be described below with reference to FIG. 9. FIG. 9 is aflowchart illustrating a processing procedure for reading an image ofthe document D stacked on the document tray 2 according to the presentexemplary embodiment. In a case where the document detection sensor 16is on (YES in step S1101), the processing proceeds to step S1102. If thecontrol unit 132 receives an instruction for starting a document readingoperation by the user (YES in step S1102), the processing proceeds tostep S1103 where the document tray 2 is rotated, and then to step S1104,where the document reading operation is started.

Referring to the flowchart illustrated in FIG. 8, when the elapsed timet1 from when the last document has been fed becomes equal to or longerthan the first predetermined time T1, the CPU 21 inclines the documenttray 2 to the front side. In contrast, referring to the flowchartillustrated in FIG. 9, in a case where an elapsed time t2 from when thelast document has been discharged becomes equal to or longer than asecond predetermined time T2, the CPU 21 inclines the document tray 2 tothe front side. More specifically, after the last document has been fedin step S1105, and then the last document has been discharged in stepS1106, the CPU 21 measures the elapsed time t2 from when the lastdocument has been discharged. In step S1108, the CPU 21 ends thedocument reading operation. In step S1109, the CPU 21 determines whetherthe elapsed time t2 from when the last document has been discharged isequal to or longer than the second predetermined time T2. In a casewhere the CPU 21 determines that the elapsed time t2 from when the lastdocument has been discharged is equal to or longer than the secondpredetermined time T2 (YES in step S1109), the processing proceeds tostep S1110.

As described above, the timing when the CPU 21 starts the measurement ofthe elapsed time is a timing after the document detection sensor 16detects that the document tray 2 has run out of documents D. It isdesirable that the predetermined times T1 and T2 are between more than 0second and less than 20 seconds, to enable the CPU 21 to prepare for thenext document reading operation after completion of the document readingoperation. Setting the predetermined times T1 and T2 in this way enablesthe document tray 2 to smoothly prepare to set the next document D.

According to the present exemplary embodiment, the CPU 21 performscontrol for inclining the document tray 2, based on the discharge sensor18. However, the present disclosure is not limited thereto. The documenttray 2 may be to be inclined based on various sensors included in theimage reading apparatus 103. For example, the document tray 2 may beinclined based on an elapsed time from when the back surface readingunit 15 reads an image of the document D.

According to the present exemplary embodiment, as described above, at apredetermined timing after the document detection sensor 16 detects thatthe document tray 2 (first stacking unit) has run out of documents D,the document tray 2 rotates to shift from the first state where thefeeding operation can be performed to the second state of being inclinedto the front side. This enables skipping an operation for inclining thedocument tray 2 when the next document D is set. Even in a case wherethe user holds the document D to be subjected to image reading in ahand, the user can set the document D to the document tray 2 beforeoperating the image reading apparatus 103.

Further, according to the present exemplary embodiment, the user caneasily take out the document D from the discharge tray 3. This isbecause the document tray 2 maintains the state illustrated in FIG. 5for 10 seconds from when the last document is fed. More specifically,since the document tray 2 is disposed above the discharge tray 3, thedocument tray 2 disturbs the user's action to take out the document Dfrom the discharge tray 3 if the document tray 2 shifts to the state ofbeing inclined to the front side illustrated in FIG. 4 before thedocument D is removed from the discharge tray 3. On the other hand,according to the present exemplary embodiment, the document tray 2 is ina state where the position of the document abutment portion 2 b israised for 10 seconds from when the last document is fed. This makes iteasier for the user to take out the document D from the discharge tray3.

As illustrated in FIG. 6, this configuration enables the document tray 2to freely rotate in a state where the clutch is disengaged. Even in acase where the document tray 2 is inclined before the user takes out thedocument D from the discharge tray 3, this configuration enables theuser to raise the front side of the document tray 2 in a direction (adirection of an arrow G in FIG. 6) and take out the document D from thedischarge tray 3. The document tray 2 may be configured to freely rotateonly in the direction with which the front side of the document tray 2is raised by using a gear with a one-way clutch instead of the gear 11 awith a clutch. In this case, it is necessary to detect whether the frontside of the document tray 2 is raised at fixed intervals aftercompletion of the flowcharts in FIGS. 8 and 9. When a state where thefront side of the document tray 2 is raised is detected, the CPU 21performs control for shifting the document tray 2 to the second state.

According to the configuration of the present disclosure, a documenttray rotates at a predetermined timing after a first detection unitdetects that a first stacking unit has run out of documents D, wherebyan image reading apparatus having high operability can be provided.

Embodiment(s) of the present disclosure can also be realized by acomputer of a system or apparatus that reads out and executes computerexecutable instructions (e.g., one or more programs) recorded on astorage medium (which may also be referred to more fully as a‘non-transitory computer-readable storage medium’) to perform thefunctions of one or more of the above-described embodiment(s) and/orthat includes one or more circuits (e.g., application specificintegrated circuit (ASIC)) for performing the functions of one or moreof the above-described embodiment(s), and by a method performed by thecomputer of the system or apparatus by, for example, reading out andexecuting the computer executable instructions from the storage mediumto perform the functions of one or more of the above-describedembodiment(s) and/or controlling the one or more circuits to perform thefunctions of one or more of the above-described embodiment(s). Thecomputer may include one or more processors (e.g., central processingunit (CPU), micro processing unit (MPU)) and may include a network ofseparate computers or separate processors to read out and execute thecomputer executable instructions. The computer executable instructionsmay be provided to the computer, for example, from a network or thestorage medium. The storage medium may include, for example, one or moreof a hard disk, a random-access memory (RAM), a read-only memory (ROM),a storage of distributed computing systems, an optical disk (such as acompact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™),a flash memory device, a memory card, and the like.

While the present disclosure has been described with reference toexemplary embodiments, it is to be understood that the disclosure is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2020-095456, filed Jun. 1, 2020, which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An image reading apparatus comprising: a firststacking unit having a stacking surface on which a document is to bestacked, and an abutment portion on which an end of the document in awidthwise direction of the document stacked on the stacking surfaceabuts; a feeding unit configured to feed the document stacked on thefirst stacking unit in a feeding direction perpendicularly intersectingthe document widthwise direction; a reading unit configured to read animage of the document fed by the feeding unit; a second stacking unitconfigured to receive the document read by the reading unit anddischarged to the second stacking unit; a first detection unitconfigured to detect presence or absence of the document on the firststacking unit; a rotating shaft extended in the feeding direction andconfigured to rotatably support the first stacking unit; a drive unitconfigured to rotate the first stacking unit around the rotating shaft;and a control unit configured to control the drive unit, wherein, at apredetermined timing after the first detection unit detects the absenceof the document on the first stacking unit, the control unit controlsthe drive unit to rotate the first stacking unit in a direction withwhich the abutment portion is lowered.
 2. The image reading apparatusaccording to claim 1, wherein the predetermined timing is a time after afirst predetermined time has elapsed from when the first detection unitdetects the absence of the document on the first stacking unit.
 3. Theimage reading apparatus according to claim 2, wherein the firstpredetermined time is between more than 0 seconds and less than 20seconds.
 4. The image reading apparatus according to claim 1, furthercomprising a second detection unit configured to detect that thedocument fed by the feeding unit has been discharged to the secondstacking unit, wherein the predetermined timing is a time after thesecond detection unit detects that a last document stacked on the firststacking unit has been discharged to the second stacking unit.
 5. Theimage reading apparatus according to claim 4, wherein the predeterminedtiming is a time after a second predetermined time has elapsed from whenthe second detection unit detected that the last document stacked on thefirst stacking unit had been discharged to the second stacking unit. 6.The image reading apparatus according to claim 1, wherein, in a casewhere the drive unit rotates the first stacking unit around the rotatingshaft, the first stacking unit is shifted from a first state where afeeding operation can be performed by the feeding unit to a second statewhere a position of the abutment portion is lower than the position ofthe abutment portion in the first state and the feeding operation cannotbe performed by the feeding unit, and wherein the control unit isconfigured to control to the drive unit to shift the first stacking unitfrom the first state to the second state.
 7. The image reading apparatusaccording to claim 1, further comprising an operation unit configured toaccept a reading start instruction, wherein the abutment portion isdisposed on an operation unit side of the first stacking unit.
 8. Theimage reading apparatus according to claim 7, wherein, based on theacceptance of the reading start instruction by the operation unit, thecontrol unit controls the drive unit to rotate the first stacking unitin a direction with which the abutment portion is raised.
 9. The imagereading apparatus according to claim 1, wherein the abutment portion isfixed to the first stacking unit.
 10. The image reading apparatusaccording to claim 1, wherein the second stacking unit is disposed belowthe first stacking unit.
 11. The image reading apparatus according toclaim 1, wherein a gear with a clutch is provided on the same axis ofthe rotating shaft.
 12. An image reading apparatus comprising: a firststacking unit having a stacking surface on which a document is to bestacked, and an abutment portion on which an end of the document in awidthwise direction of the document stacked on the stacking surfaceabuts; a feeding unit configured to feed the document stacked on thefirst stacking unit in a feeding direction perpendicularly intersectingthe document widthwise direction; a reading unit configured to read animage of the document fed by the feeding unit; a second stacking unitconfigured to receive the document read by the reading unit anddischarged; a first detection unit configured to detect presence orabsence of the document on the first stacking unit; a rotating shaftextended in the feeding direction and configured to rotatably supportthe first stacking unit; a drive unit configured to rotate the firststacking unit around the rotating shaft; and a control unit configuredto control the drive unit, wherein, at a downstream end in the feedingdirection, the stacking surface has a first edge and a second edge,where the first edge is close to the abutment portion in the documentwidthwise direction and the second edge is distant from the abutmentportion in the document widthwise direction in comparison with the firstedge, and wherein, at a predetermined timing after the first detectionunit detects that the first stacking unit has run out of the document,the control unit controls the drive unit to rotate the first stackingunit in a direction with which the first edge becomes lower than thesecond edge.
 13. The image reading apparatus according to claim 12,wherein the predetermined timing is a time after a first predeterminedtime has elapsed from when the first detection unit detects the absenceof the document on the first stacking unit.
 14. The image readingapparatus according to claim 12, further comprising a second detectionunit configured to detect that the document fed by the feeding unit hasbeen discharged to the second stacking unit, wherein the predeterminedtiming is a time after the second detection unit detects that a lastdocument stacked on the first stacking unit has been discharged to thesecond stacking unit.
 15. The image reading apparatus according to claim14, wherein the predetermined timing is a time after a secondpredetermined time has elapsed from when the second detection unitdetected that the last document stacked on the first stacking unit hadbeen discharged to the second stacking unit.
 16. The image readingapparatus according to claim 12, further comprising an operation unitconfigured to accept a reading start instruction, wherein the abutmentportion is disposed on an operation unit side of the first stackingunit.
 17. The image reading apparatus according to claim 16, wherein,based on the acceptance of the reading start instruction by theoperation unit, the control unit controls the drive unit to rotate thefirst stacking unit in a direction with which the first edge becomeshigher than the second edge.
 18. The image reading apparatus accordingto claim 12, wherein a gear with a clutch is provided on the same axisof the rotating shaft.
 19. An image forming apparatus comprising: afirst stacking unit having a stacking surface on which a document is tobe stacked, and an abutment portion on which an end of the document in awidthwise direction of the document stacked on the stacking surfaceabuts; a feeding unit configured to feed the document stacked on thefirst stacking unit in a feeding direction perpendicularly intersectingthe document widthwise direction; a reading unit configured to read animage of the document fed by the feeding unit; a second stacking unitconfigured to receive the document read by the reading unit anddischarged to the second stacking unit; a first detection unitconfigured to detect presence or absence of the document on the firststacking unit; a rotating shaft extended in the feeding direction andconfigured to rotatably support the first stacking unit; a drive unitconfigured to rotate the first stacking unit around the rotating shaft;a control unit configured to control the drive unit, and an imageforming unit configured to form an image on a recording material basedon the image read by the reading unit, wherein, at a predeterminedtiming after the first detection unit detects the absence of thedocument on the first stacking unit, the control unit controls the driveunit to rotate the first stacking unit in a direction with which theabutment portion is lowered.
 20. A method for an image reading apparatusthat includes a first stacking unit having a stacking surface on which adocument is to be stacked, and an abutment portion on which an end ofthe document in a widthwise direction of the document stacked on thestacking surface abuts, and having a second stacking unit and a rotatingshaft extended in a feeding direction, the method comprising: feedingthe document stacked on the first stacking unit in the feeding directionperpendicularly intersecting the document widthwise direction; readingan image of the fed document; receiving, on the second stacking unit,the read document discharged to the second stacking unit; detecting, asa first detection, presence or absence of the document on the firststacking unit; rotatably supporting the first stacking unit by therotating shaft; rotating the first stacking unit around the rotatingshaft; and controlling the rotating of the first stacking unit aroundthe rotating shaft, wherein, at a predetermined timing after the firstdetection detects the absence of the document on the first stackingunit, controlling includes rotating the first stacking unit in adirection with which the abutment portion is lowered.
 21. Anon-transitory computer-readable storage medium storing a program tocause a computer to perform a method for an image reading apparatus thatincludes a first stacking unit having a stacking surface on which adocument is to be stacked, and an abutment portion on which an end ofthe document in a widthwise direction of the document stacked on thestacking surface abuts, and having a second stacking unit and a rotatingshaft extended in a feeding direction, the method comprising: feedingthe document stacked on the first stacking unit in the feeding directionperpendicularly intersecting the document widthwise direction; readingan image of the fed document; receiving, on the second stacking unit,the read document discharged to the second stacking unit; detecting, asa first detection, presence or absence of the document on the firststacking unit; rotatably supporting the first stacking unit by therotating shaft; rotating the first stacking unit around the rotatingshaft; and controlling the rotating of the first stacking unit aroundthe rotating shaft, wherein, at a predetermined timing after the firstdetection detects the absence of the document on the first stackingunit, controlling includes rotating the first stacking unit in adirection with which the abutment portion is lowered.